Apparatus for making filter tip cigarettes



Jan. 7, 1969 c. s. M ARTHUR 3,420,243

APPARATUS FOR MAKING FILTER TIP CIGARETTES Filed Jan. 5, 1967 Sheet of 2INVENTOR.

Coy/v 5. McAWrHz/R Jan. 7, 1969 c, s. MCARTHUR 3,420,243

APPARATUS FOR MAKING FILTER TIP CIGARETTES Filed Jan. 5 l967 Sheet g of2 l N VE NTOR. Cou/v 5. Nc/Jmwue ATTORNEY United States Patent Ofitice3,420,243 Patented Jan. 7, 1969 13 Claims ABSTRACT OF THE DISCLOSUREApparatus and method for covering assembled cigarette units (eachcomprising at least one cigarette rod section and at least one filtersection) with patches of tipping material coated with heat-activatableadhesive. The patch is first heated, then its leading edge is applied tothe assembled cool unit so as to span abutting ends of rod and filtersections. Local cooling of the adhesive completes the bond. The unitwith the attached patch is then cooled, rolled for a partial revolutionwhile cool, then rolled for plural revolutions on a heated shoe whichreactivates the adhesive, and finally rolled for plural revolutions onan unheated shoe to freeze the adhesive.

Backgroimd the invention In the manufacture of filter tip cigarettes, ithas been the practice in the past to assemble a section of cigarette rodwith a section of filter material, and to connect the two sections bywrapping around their abutting ends a patch of sheet material, commonlycalled tipping material. This tipping material is coated with a liquidbonding agent before it is wrapped around the cigarette unit,

and the bond is set by drying the liquid bonding agent after theconnection is completed. The handling of the tipping maerial coated withthe liquid bonding agent entails some spilling of the bonding material,with the resultant necessity to stop the machine occasionally to cleanup the spilled material.

There have been available for many years, a class of heat-activatable(or heat-sealing) bonding materials, which are dry at room temperatures,but which are rendered tacky by heating to about l50-200 F. Thesematerials have not heretofore been used for manufacturing filter tipcigarettes, because the machinery of the prior art has not been adaptedto heating the material before the bonding, and cooling it after thebonding. Furthermore, when such a bonding material is used, the bond isnot secure until the bonding material is cooled. Consequently, there isa tendency for the bond to separate after it is initially formed, withthe result that the finished cigarette is defective.

Summary of the invention The present invention uses patches of tippingmaterial coated with heat-activatable bonding material. It overcomes thedifiiculties encountered in the prior art by first tacking one edge of aheated patch of bonding material to an assembled cigarette and filterunit. This tacking is accomplished without any immediately followingattempt to roll the cigarette and to wrap it in the tipping material.The cigarette then travels along an unheated path for a distancesufiicient to cool the bonding material and allow the initial tack toset. Thereafter the cigarette is rolled through a partial revolution soas to bring the initial tack to an angular position where it is out ofalignment with a heating shoe that is next engaged by the cigarette andis effective to roll it through a plurality of revolutions, therebyheating the bonding material and making it tacky throughout the patch oftipping material. Finally, the

cigarette is rolled over another unheated rolling shoe which iseffective to cool the bonding material and set the bond.

Description of the drawing FIG. 1 is a somewhat diagrammatic viewillustrating the apparatus and method of the invention;

FIG. 2 is a series of four successive perspective views of a cigaretteunit as it is handled in the apparatus and method of the invention;

FIG. 3 is an enlarged cross-sectional view of a patch heating drumforming part of the apparatus of the invention;

FIG. 4- is an enlarged view partly in perspective, taken from below, andpartly in central cross-section, showing the rolling shoe of FIG. 1;

FIG. 5 is an enlarged cross-sectional view showing the initial contactbetween the cigarette units on a transfer drum and the patches on thepatch heating drum;

FIG. 6 is a view similar to FIG. 5, showing the cigarette unit with tackpatch connected, moving along the transfer drum after separation fromthe heating drum;

FIG. 7 shows the assembled unit on the periphery of the rolling drum;

FIG. 8 is a view showing the cigarette on the periphery of the rollingdrum as it rnoves into contact with the initial section of the rollingshoe;

FIG. 9 is a view similar to FIG. 8, but showing the cigarette as itpasses the end of the initial section of the rolling shoe;

FIG. 10 is a view similar to FIG. 9, showing the movement of thecigarette as it passes under the heated section of the rolling shoe.

Description of the preferred embodiment The apparatus illustrated inFIG. 1 includes a tipping material heating drum 1, a cutter 2,cooperating with that drum, a transfer drum 3 to which assembled filtercigarette units are supplied by conventional apparatus, not shown, arolling drum 5 and a rolling shoe cooperating with the rolling drum andgenerally indicated at 6.

The tipping material is supplied as a strip or sheet, as illustrated at7, and passes around the periphery of the heating drum 1. The material 7is coated on its outer surface with a suitable heat-activatable bondingmaterial, e.g., one of the vinyl acetate acryliccopolyrners. The drum 1is provided with spaced apertures 1a which communicate with an evacuatedchamber, and which are effective to hold the strip material 7 on thesurface of the drum. The drum 1 cooperates with a cutter 2 which cutsthe strip material into patches 8, each big enough to wrap a singlecigarette. The drum 1 is operated at a peripheral speed slightly greaterthan the linear speed of the supply of the strip material 7 so that thepatches 8 become separated on the surface of the drum 1, as shown. Eachcigarette unit 11 typically consists of a double length filter section,as shown at 9 in FIG. 2 and two cigarette rod sections 10, with eachcigarette rod section having one of its ends abutting an end of thefilter section 9. The term cigarette unit as used in this specificationis intended to be generic to: (a) such a double length unit; and (b)single length units as shown at 13.

The transfer drum 3 and the heater drum 1 are so mounted and spaced thateach cigarette unit 11, which is held in a recess 3:: by vacuum means onthe periphery of the transfer drum 3, touches tangentially and withlight pressure the leading edge of one of the patches 8 carried by theheater drum 1. At the same time, the apertures 1a under that leadingedge pass out of communication with a vacuum manifold 12 so that thetipping patch, whose heat-activatable bonding material has become tackyby the effect of the heat of the drum 1, sticks to the abuttingcigarette unit along one elongated cylindrical element thereof. Thepatch is gradually released from the heater drum as the rotation of thatdrum and the transfer drum continues, so that the cigarette unit 11continues with the periphery of the transfer drum 3, having the patch 8attached thereto and following behind it. The transfer drum 3 cooperatestangentially with a rolling drum 5 also provided with recesses 5a toreceive cigarette units. Each recess 5a communicates with a passage 5b,in which a vacuum is maintained to hold the cigarette units on theperiphery of the drum. The recesses 5a are somewhat shallower thancorresponding recesses 3a on the transfer drum, so as to make it easierfor the rolling mechanism to begin to roll a cigarette unit out of oneof the recesses 5a. Preferably, the depth of each recess 5a is about0.015". This depth is exaggerated in the drawing, for purposes ofclarity. As the cigarette unit with attached patch 8 approaches the topof the rolling drum 5, it encounters the rolling shoe 6 which comprisesan initial unheated section 6a separated by an insulating spacer 6b froma heated rolling section 6c. The section 6c and the opposite end of theshoe are separated by another heat insulating spacer 6d from a third,unheated rolling shoe section 6e.

The heated shoe section 6c is somewhat narrower than the unheatedsections 6a and 6e, being just slightly wider than the patch 8 which itis intended to heat. The section 60 is flanked on either side by anotherunheated section 6 one of which is shown in FIG. 4, so that the entirelength of the cigarette unit is rolled evenly, while only the patch 8 issubjected to heat.

The bottom of the shoe 6 is provided with a plurality of ridges 6g,extending parallel to the axis of rotation of drum 5. The ridges 6g arespaced apart along the arcuate surface of the shoe 6, so that thecentral angle at the axis of drum 5, between radii drawn to the centersof successive ridges, is equal to the central angle between the centersof successive recesses 5a. The ridges 6g project from the surface ofshoe 6 by a distance slightly greater than the depth of a recess 5a. Thepurpose of each ridge 6g is to engage the periphery of a passingcigarette unit resting in one of the recesses 5a, and start it rollingout of that recess, and between the periphery of the drum 5 and thearcuate surface of the shoe 6.

The ridges 6g are preferably provided with angular edges, as shown, togive them a good grip on the periphcries of passing cigarettes.

Each cigarette rolling between the shoe 6 and drum 5 moves at one-halfthe peripheral speed of drum 5. Hence, there are twice as manycigarettes under the shoe 6 as there are recesses 5a, at any given time.

The first ridge 6g is at the leading edge of the shoe section 6a, andthe locations of the others are determined by the angular relationshipdescribed above. With this spacing of the ridges, each time that acigarette falls into a recess 5a, it soon thereafter encounters a ridgeeffective to roll out of that recess. The spacers 6b and 6d may eitherbe of solid, heat insulating material, or may simply be an air space,which has adequate heat insulating qualities for the purpose. Where anair space is used, the ends of the cigarette unit, being rolled betweenthe drum and the unheated sections 6 of the shoe 6, keep the cigaretterolling as it crosses the gap at the spacers 6b and 6d.

The shoe 6 is separated from the periphery of drum 5 by a distanceslightly less than the diameter of a cigarette unit, so that when thecigarette unit 11 encounters the initial shoe section 6a, it is rolledout of its associated recess 5a, by ridge 6g, as shown in FIG. 8. Thevacuum in the passage 5b is released at the same time, by conventionalmeans. The peripheral length of the sec tion 6a is suflicient so thatwhen the cigarette reaches the end of section 6a, it has rotated morethan one half revolution, and the tack at its leading edge has passedbeyond the point of contact with the rolling shoe 6. (See FIG. 9). Afterpassing the insulating section 6b, the cigarette unit encounters heatedshoe section 60, which is effective to roll the cigarette through aplurality of revolutions, at the same time heating the cigarette andmaking the bonding material on the inner surface of the patch tacky sothat it sticks to the cigarette rod section and the filter section.During this heating, the cigarette unit is always firmly held betweenthe drum 5 and the shoe 6, so that the patch cannot come loose. Afterthe cigarette unit passes the heater section 60 of the rolling shoe, itthen passes the insulator section 6d of the cooling section 62, wherethe cigarette is further rolled for a plurality of revolutions.

At the cooling shoe section 6e, the heat-activatable material is set bythe cooling action of the shoe. At the point where the cigarettes passfrom the cooling section 6e, the vacuum is again restored to thepassages 5b, so that the cigarettes are held by the vacuum in thenearest groove 5a and pass to further manufacturing operations, whichcommonly include cutting each unit into two individual cigarettes 13, asshown at the bottom of FIG. 2.

FIG. 3

This figure illustrates the heating drum 1 which iu cludes an outercylinder shell of hard-resistant material, for example, tungstencarbide, shown generally at 14. The passages 1a are arranged in rows,and each row communicates with a passage 15 that extends axially of thedrum. The axial passages communicate, during a portion of theirrotation, with a manifold 12 mounted on a fixed support 16, andconnected by means of a conduit 17 to a suitable source ofsubatrnospheric pressure. The outer shell 14 is mounted on an innershell 18 which is in turn mounted by means of bolts 19 to a flange 20attached to the end of a driving shaft 21.

On the right-hand outer face of the inner shell 18 is mounted aninsulating plate 22, which may be of suitable plastic material, and inwhich are embedded two sets of slip rings 23 and 24. The slip rings 24communicate through wires 25 with a heater winding 26 located internallyof the shell 18. A thermocouple 27, or other suitable temperaturesensitive element is embedded in the shell 18 and connected throughsuitable wires to the other set of slip rings 23. Brushes (not shown)cooperate with the slip rings 23 and 24. The temperature indicated bythe thermocouple 27 may be used to control the current to the heaterwinding 26 and alternatively, the temperature indication fromthermocouple 27 may be used simply to operate an indicator or recorder,and the current flow to the winding 26 may be manually controlled.

As shown in FIG. 4, the heater section 60 of the rolling shoe 6 isprovided with a heater winding 28 and with a temperature measuringthermocouple 29. The thermocouple 29 may be used for purposes analogousto those of the thermocouple 27 discussed above.

I claim:

1. Apparatus for connecting a filter tip to a cigarette, comprising:

(1) means for assembling cigarette units for tipping, each unitincluding a section of cigarette rod and a section of filter rod havingone of its ends abutting an end of the cigarette rod section;

(2) means for wrapping around the abutting ends of each assembled unit apatch of tipping material coated with bonding material to form a filtertip cigarette;

wherein the improvement comprises:

(a) means for supplying patches of tipping material coated withheat-activatable bonding material;

(b) means to heat said patches, thereby activating the bonding material;

(c) means to apply the leading edge of each heated patch to theperiphery of an assembled, unheated cigarette unit, with the patchspanning the abutting rod ends, thereby locally cooling and setting theadhesive along said leading edge and attaching the patch to the unitalong a linear element thereof;

(d) first rolling means to roll the unit with the attached patch througha partial revolution without further heating;

(e) second rolling means including:

(1) a second heating means positioned to engage initially a locality ofthe unit spaced peripherally thereof from said linear element; and

(2) means to continue the rolling of the unit for a plurality ofrevolutions while applying heat to said patch to form a completed filtertip cigarette unit.

2. Apparatus as defined in claim 1, wherein the improvement furthercomprises:

(a) third rolling means to continue rolling of the unit without heating,so as to set the bonding material.

3. Apparatus as defined in claim 1, wherein the improvement furthercom-prises means defining an unheated path of travel between the patchapplying means and the rolling means.

4. Apparatus as defined in claim 1, in which said partial revolutionrolling means is effective to roll the unit through an angle greaterthan 180.

5. Apparatus as defined in claim 1, in which said patch heating meanscomprises a heated drum and vacuum means to hold the patches on thesurface of the drum with their coated surfaces outward.

6. Apparatus as defined in claim 5, in which the patch applying meansincludes:

(a) a transfer drum;

(b) vacuum means in said transfer drum to hold the assembled units onthe periphery thereof;

(c) said transfer drum being spaced from the heating drum so that saidassembled units on the transfer drum and the heated patches on theheating drum approach one another tangentially.

7. Apparatus as defined in claim 6, including:

(a) vacuum release means on the heated drum effective to release eachpatch therefrom upon contact of an assembled cigarette unit with theleading edge of the patch.

8. Apparatus as defined in claim 1, in which said first rolling meanscomprises:

(a) a rolling drum having shallow recesses in its periphery forreceiving said cigarette units;

(b) vacuum means in said rolling drum for lightly retaining said unitsin said shallow recesses; and

(c) unheated shoe means having a surface concentric with and spacedradially outwardly from the periphery of the rolling drum and meansefiective to engage units in said recesses and roll them along the drumperiphery, regardless of the retaining effect of the vacuum means.

9. Apparatus as defined in claim 8, in which said second rolling meanscomprises a heated second shoe means separated circumferentiallyrelative to said rolling drum from said unheated shoe means by a heatinsulating space, and cooperating with cigarette units leaving saidunheated shoe means and traveling on the periphery of said rolling 6drum to continue the rolling of said units for a plurality ofrevolutions while heating them.

10. Apparatus as defined in claim 9, in which said second rolling meansfurther comprises a third shoe means separated circumferentiallyrelative to the periphery of the rolling drum from said heated secondshoe means and cooperating with cigarette units leaving the heatedsecond shoe means to continue the rolling of said units, said third shoemeans being unheated and effective to cool and set the adhesive on saidunits.

11. Apparatus for wrapping an assembled cigarette unit, including asection of cigarette rod and a section of filter rod, within a patch ofsheet material coated with heat-activatable bonding materials,comprising:

(a) a drum having shallow recesses in its periphery for receivingcigarette units with patches adhering thereto along linear elementsthereof;

(b) vacuum means within the drum for holding the cigarette units in saidrecesses;

wherein the improvement comprises:

(c) first shoe means spaced radially outwardly from the periphery of thedrum, said first shoe means being unheated, and being adapted to engagecigarette units on the drum periphery and roll them through a partialrevolution as the drum rotates;

(d) second shoe means spaced radially outwardly from the periphery ofthe drum and circumferentially relative to the drum, in the direction ofrotation thereof from said first shoe means, and adapted to roll saidunits through a plurality of revolutions;

(e) means for heating said second shoe means; and

(f) third shoe means spaced radially outwardly from the periphery of thedrum and circumferentially relative to the drum in the direction ofrotation thereof, from said second shoe means, said third shoe meansbeing unheated and adapted to engage cigarette units leaving said secondshoe means and effective to roll said cigarette units through aplurality of revolutions.

12. Apparatus as defined in claim 11, in which said first, second andthird shoe means comprises a unitary shoe with first, second and thirdsections corresponding respectively to said three shoe means andseparated from one another by heat insulating spaces.

13. Rolling shoe means for use in apparatus for wrapping cigarette unitsin patches coated with heat-activatable bonding material, wherein theimprovement comprises:

(a) a unitary shoe having first, second and third sections separated byheat insulating spaces; and

(b) heater means associated with said second section.

References Cited UNITED STATES PATENTS 2,984,245 5/ 196 1 Phillips 131943,094,128 6/1963 Dearsley 131-94 FOREIGN PATENTS 1,183,000 12/1964Germany. 1,881,457 10/ 1963 Germany.

345,287 4/ 1960 Switzerland.

SAMUEL KOREN, Primary Examiner.

J. H. CZERWONKY, Assistant Examiner.

U.S. Cl. X.R. 156499, 578

